Law professor Robert Jackson is the Trump administration’s pick to fill the open Democratic seat at the Securities and Exchange Commission, raising the chances that Wall Street’s main regulator will have a full complement of commissioners for the first time since 2015.

The White House announced Friday that President Donald Trump nominated Jackson, who directs the Columbia University Law School’s Program on Corporate Law and Policy, for the slot. In July, the administration announced it would nominate Hester Peirce, a former Senate staff member whom the Obama administration also picked, to fill the open Republican position at the SEC. It’s common for the Senate to consider Republican and Democratic nominees together for confirmation.

While SEC Chairman Jay Clayton, who took over in May, will direct much of the agency’s agenda, major rulemaking and enforcement actions require approval by a majority of commissioners. Clayton is expected to generally back Trump’s agenda to roll back post-crisis financial rules, and having a full slate of commissioners gives him more room to maneuver and forge alliances to work on policy.

For his part, Jackson has long urged the SEC to draft rules requiring public companies to disclose political donations. Democratic senators, led by Chuck Schumer of New York and Elizabeth Warren of Massachusetts, chastised the former chairwoman, Mary Jo White, for not beginning work on such regulations. Republicans have opposed the potential measure, which has been decried by the U.S. Chamber of Commerce and other large business groups.